Is there any update on this? I have TFS 2015 Update 2.1 and even when I MANUALLY delete a completed BUILD it still does not clean up the files on my UNC Drop Location. I have a "Copy and Publish Build Artifacts" task with a path of \\servername\Deployment_Requests\BW.Application\$(Build.DefinitionName)_$(Build.BuildNumber). I even tried fully qualifying servername.domain and it still didn't delete the files that were published to Drop Location. This is really annoying because we have to manually clean up drop location files even after the BUILD is deleted. When manually deleting the build it prompts saying, "Are you sure you want to delete everything about build XYZ including details, FILES AND FOLDER UNDER DROP FOLDER, test results, symbols and label". This implies that it will delete DROP FOLDER files but it does not. I don't see any info in logs either. This needs fixed in both Retention Policy and Manual Deletion of Builds.